Semi-Adaptive Vibration Controller for Generating the Target Acceleration of the Subsystem in a Prototype Car

This research aims to develop an inverse controller to track target vibration signals for the application to car subsystem evaluations. In recent times, perceptive assessments of car vibration have been technically significant, particularly parts interacting with passengers in the car such as steering wheels and seats. Conventional vibration test methods make it hard to track the target vibration signals in an accurate manner without compensating for the influence of the transfer function. Hence, this paper researched the vibration tracking system based on inverse system identification and digital signal processing technologies. Specifically, the controller employed a semi-active algorithm referring to both the offline modeling of the inverse system and the adaptive control. The semi-active controller could reconstruct the target vibration signal in a more efficient and safer way. The proposed methodology was first confirmed through computation simulations using Simulink. The simulation results verified that the semi-active controller could outperform the conventional active controller with respect to converging speed and stability. Following the simulation studies, actual vibration tests validated the suggested method in a steering wheel. A weight disturbance of about 0.24 kg was attached to the steering wheel to realize the possible change in the system characteristics. The semi-active controller could successfully track target vibration, such as a single or a dual harmonic signal, at the target spot of the steering wheel within the control error of about 1.6 dB regardless of the variation of the system transfer function. The proposed semi-active controller will provide an accurate, efficient tracking of vibrations in the evaluation of car subsystems.